中文摘要：

考虑晶体生长界面的变形,利用有限体积方法对侧面加热的空间全浮区法硅单晶生长中熔区内的热质传输、流场及晶体生长界面位置和形态特征进行了数值研究。应用不同中等强度的轴向磁场和勾型磁场对硅熔体内的热毛细对流进行抑制。分析了静态磁场不同强度下熔区中的对流模式,研究表明,轴向和勾型磁场均能有效抑制熔体内的对流,并将热毛细对流挤压到自由表面附近。轴向磁场可有效抑制熔体的径向流动,但难以有效抑制轴向对流;勾型磁场则可以达到更好的控制熔体对流的效果。对不同强度下的固液面形态及位置分析发现：轴向磁场下固液面基本和无磁场时的重合,但磁场强度较小时固液面在自由表面边缘处向单晶侧有个凸起;勾型磁场作用下的固液面比较平滑,其中心区域较无磁场时整体向z轴正向偏移。研究结果可对浮区法晶体生长中获得高质量晶体提供帮助。

英文摘要：

Considering the interfacial deformation of crystal growth,the characteristics of heat and mass transfer,fluid flow and the site and shape of the melt / solid interfaces in molten zone were solved numerically by finite-volume method for a full floating-zone model subjected to be lateral heated under microgravity. The applications of both axial and cusp magnetic fields of moderate strength to suppress the thermocapillary convection in the melt during silicon crystal growth were addressed. The flow pattern in the floating zone under the effect of static magnetic fields was performed. It is observed that both axial and cusp magnetic fields suppress the convection in the core region effectively, and squeeze the thermocapillary flow area toward the free surface. Furthermore,the results demonstrate that the axial magnetic field can help to suppress melt flow in the radial direction; however,it is difficult to restrain the axial convection effectively. The coupled favorable effect,weakened melt flow in both axial and radial direction with an axisymmetrical convection structure,is obtained under cusp magnetic field. The site and shape of the melt / solid interfaces were analyzed as well under different magnetic field strength. It isfound that the melt / solid interfaces coincide with each other with and without axial magnetic fields,yet the melt / solid interfaces are convex toward single crystal at the edge of the free surface when the axial magnetic fields are relatively weaker,while in the cusp magnetic fields the melt / solid interfaces become very smooth,and the central regions of which move,as a whole,to the positive z axis. The results can provide the help to obtain high quality crystal growth in floating zone method.